Bug 554822 Caret should refer the actual text color instead of the value of CSS color property r=roc

layout/base/nsCaret.cpp

@@ -497,7 +497,7 @@ nsresult nsCaret::DrawAtPosition(nsIDOMNode* aNode, PRInt32 aOffset)
   return rv;
 }
 
-nsIFrame * nsCaret::GetCaretFrame()
+nsIFrame * nsCaret::GetCaretFrame(PRInt32 *aOffset)
 {
   // Return null if we're not drawn to prevent anybody from trying to draw us.
   if (!mDrawn)
@@ -505,14 +505,17 @@ nsIFrame * nsCaret::GetCaretFrame()
 
   // Recompute the frame that we're supposed to draw in to guarantee that
   // we're not going to try to draw into a stale (dead) frame.
-  PRInt32 unused;
+  PRInt32 offset;
   nsIFrame *frame = nsnull;
   nsresult rv = GetCaretFrameForNodeOffset(mLastContent, mLastContentOffset,
                                            mLastHint, mLastBidiLevel, &frame,
-                                           &unused);
+                                           &offset);
   if (NS_FAILED(rv))
     return nsnull;
 
+  if (aOffset) {
+    *aOffset = offset;
+  }
   return frame;
 }
 
@@ -545,7 +548,10 @@ void nsCaret::PaintCaret(nsDisplayListBuilder *aBuilder,
   NS_ASSERTION(mDrawn, "The caret shouldn't be drawing");
 
   const nsRect drawCaretRect = mCaretRect + aOffset;
-  nscolor cssColor = aForFrame->GetStyleColor()->mColor;
+  PRInt32 contentOffset;
+  nsIFrame* frame = GetCaretFrame(&contentOffset);
+  NS_ASSERTION(frame == aForFrame, "We're referring different frame");
+  nscolor foregroundColor = aForFrame->GetCaretColorAt(contentOffset);
 
   // Only draw the native caret if the foreground color matches that of
   // -moz-fieldtext (the color of the text in a textbox). If it doesn't match
@@ -559,7 +565,7 @@ void nsCaret::PaintCaret(nsDisplayListBuilder *aBuilder,
       nsILookAndFeel* lookAndFeel = presContext->LookAndFeel();
       nscolor fieldText;
       if (NS_SUCCEEDED(lookAndFeel->GetColor(nsILookAndFeel::eColor__moz_fieldtext, fieldText)) &&
-          fieldText == cssColor) {
+          fieldText == foregroundColor) {
         theme->DrawWidgetBackground(aCtx, aForFrame, NS_THEME_TEXTFIELD_CARET,
                                     drawCaretRect, drawCaretRect);
         return;
@@ -567,7 +573,7 @@ void nsCaret::PaintCaret(nsDisplayListBuilder *aBuilder,
     }
   }
 
-  aCtx->SetColor(cssColor);
+  aCtx->SetColor(foregroundColor);
   aCtx->FillRect(drawCaretRect);
   if (!GetHookRect().IsEmpty())
     aCtx->FillRect(GetHookRect() + aOffset);

layout/base/nsCaret.h

@@ -136,8 +136,10 @@ class nsCaret : public nsISelectionListener
      *  Get the current frame that the caret should be drawn in. If the caret is
      *  not currently visible (i.e., it is between blinks), then this will
      *  return null.
+     *
+     *  @param aOffset is result of the caret offset in the content.
      */
-    nsIFrame*     GetCaretFrame();
+    nsIFrame*     GetCaretFrame(PRInt32 *aOffset = nsnull);
 
     /** GetCaretRect
      *  Get the current caret rect. Only call this when GetCaretFrame returns

layout/generic/nsFrame.cpp

@@ -973,6 +973,13 @@ nsIFrame::DisplayCaret(nsDisplayListBuilder* aBuilder,
       new (aBuilder) nsDisplayCaret(this, aBuilder->GetCaret()));
 }
 
+nscolor
+nsIFrame::GetCaretColorAt(PRInt32 aOffset)
+{
+  // Use text color.
+  return GetStyleColor()->mColor;
+}
+
 PRBool
 nsIFrame::HasBorder() const
 {

layout/generic/nsIFrame.h

@@ -977,6 +977,13 @@ public:
                         const nsRect&               aDirtyRect,
                         nsDisplayList*              aList);
 
+  /**
+   * Get the preferred caret color at the offset.
+   *
+   * @param aOffset is offset of the content.
+   */
+  virtual nscolor GetCaretColorAt(PRInt32 aOffset);
+
   PRBool IsThemed(nsTransparencyMode* aTransparencyMode = nsnull) {
     return IsThemed(GetStyleDisplay(), aTransparencyMode);
   }

layout/generic/nsTextFrame.h

@@ -307,6 +307,8 @@ public:
                                      SelectionDetails* aDetails,
                                      SelectionType aSelectionType);
 
+  virtual nscolor GetCaretColorAt(PRInt32 aOffset);
+
   PRInt16 GetSelectionStatus(PRInt16* aSelectionFlags);
 
 #ifdef DEBUG

layout/generic/nsTextFrameThebes.cpp

@@ -4717,6 +4717,48 @@ nsTextFrame::PaintTextWithSelection(gfxContext* aCtx,
   return PR_TRUE;
 }
 
+nscolor
+nsTextFrame::GetCaretColorAt(PRInt32 aOffset)
+{
+  NS_PRECONDITION(aOffset >= 0, "aOffset must be positive");
+
+  gfxSkipCharsIterator iter = EnsureTextRun();
+  PropertyProvider provider(this, iter);
+  PRInt32 contentOffset = provider.GetStart().GetOriginalOffset();
+  PRInt32 contentLength = provider.GetOriginalLength();
+  NS_PRECONDITION(aOffset >= contentOffset &&
+                  aOffset <= contentOffset + contentLength,
+                  "aOffset must be in the frame's range");
+  PRInt32 offsetInFrame = aOffset - contentOffset;
+  if (offsetInFrame < 0 || offsetInFrame >= contentLength) {
+    return nsFrame::GetCaretColorAt(aOffset);
+  }
+
+  nsTextPaintStyle textPaintStyle(this);
+  SelectionDetails* details = GetSelectionDetails();
+  SelectionDetails* sdptr = details;
+  nscolor result = nsFrame::GetCaretColorAt(aOffset);
+  SelectionType type = 0;
+  while (sdptr) {
+    PRInt32 start = NS_MAX(0, sdptr->mStart - contentOffset);
+    PRInt32 end = NS_MIN(contentLength, sdptr->mEnd - contentOffset);
+    if (start <= offsetInFrame && offsetInFrame < end &&
+        (type == 0 || sdptr->mType < type)) {
+      nscolor foreground, background;
+      if (GetSelectionTextColors(sdptr->mType, textPaintStyle,
+                                 sdptr->mTextRangeStyle,
+                                 &foreground, &background)) {
+        result = foreground;
+        type = sdptr->mType;
+      }
+    }
+    sdptr = sdptr->mNext;
+  }
+
+  DestroySelectionDetails(details);
+  return result;
+}
+
 static PRUint32
 ComputeTransformedLength(PropertyProvider& aProvider)
 {